Printing on plastic or polymer object surfaces and on some metal surfaces with UV curable inks is often a challenge because the ink may not adhere properly to the surface. This lack of adhesion is due to the surface energy of the substrate being too close to the surface tension of the ink with the result that surface wets poorly. Ideally the surface energy of the substrate should be much higher than the surface tension of the ink to enable the ink to wet the surface properly. One method of raising the surface energy of a polymer or metal substrate is to subject the surface to an electrical discharge or plasma, which is known to affect the surface chemically and produce a higher surface energy. Previously known plasma treatment devices, however, tend to be very expensive, may require chambers to maintain specific atmospheric conditions, or are rigid and cannot conform to contoured surfaces for treatment of the surfaces. A plasma surface treatment device that is low cost and flexible and that works in normal atmospheric conditions would be beneficial.